Fog-projecting fire extinguisher construction



A. JACOBS Aug. 10, 1965 FOG-PROJECTING FIRE EXTINGUISHER CONSTRUCTION Filed April 17, 1962 INVENTOR. J44 91v cl' coss /7rra -sys.

United States ill The present invention relates generally to apparatus for extinguishing fires by means of a combustion-smothering and cooling fog or mist propelled by a compressed liquefied nonfiammable gas such as carbon dioxide, and more specifically relates to novel improvements on the types of extinguisher genrally exemplified by my Patent 2,755,865, issued July 24, 1956, and my Patent 2,832,425, issued Apr. 29, 1958.

The present invention provides means for producing and projecting a fog of readily vaporizable liquid, and may be embodied in either of two principal forms. In accordance with the preferred form of the invention, means are provided for permitting selective starting and stopping of the projected fog. Thus the extinguisher may be used to put out a number of fires over a period of time on a single charge. In another form of the invention, the extinguisher is arranged to completely empty itself after being once started; it must accordingly be recharged after each use.

In both forms of the invention there is provided an improved form of gun including a nozzle for thoroughly intermixing a liquefied nonfiammable gas, typically carbon dioxide, and a liquid, typically water, to form a fog in order to permit ready vaporization of the liquid rapid- 1y, thereby permitting the heat of vaporization of the liquid to be availed of in lowering the temperature in the region of the fire. This factor, together with the substantial exclusion of oxygen from the fire by reason of the existence of the fog and resultant vapor or steam, combines to make an extremely efiective means for extinguishing the fire. In addition, it has been found that substantially improved fire extinguishing results are obtained by mixing with the water in its housing tank a quantity of material such as methyl alcohol which is itself flammable, or in general a hydrogen producing compound. The effect of using the miscible flammable material is to increase the rapidity and thoroughness of dispersion of the water into a fog or mist when the flam- Inable material is ignited by the fire, thereby further hastening the absorption or" the major amount of heat in the tire zone by the heat of vaporation of the water. Thus the extreme rapidity with which the temperature is lowered in the fire zone compensates for the added heat resulting from the burning of the flammable material mixed with the water. The proportion of flammable material added to the water may, in the case or" methyl alcohol, be about three to ten percent by weight, preferably about five percent. However, the proportion may be increased very substantially, to the neighborhood of half, which permits the extinguisher to be ready for instant use even when stored in sub-freezing temperatures, since the aqueous mixture in the tank can have a much lower freezing point than water alone.

The improved mixing of the nonfiarnmable liquefied gas under high pressure with the water is accomplished in a gun including a nozzle forming part of the invention. In accordance with the invention, the gun nozzle includes a barrel having an inside diameter of between about onehalf and one inch and, coaxially mounted therein, a gas supply tube terminating in a multi-port-ed outlet member. The forward end of the outlet member is desirably recessed from the forward end of the barrel by a distance approximately equal to the inside diameter of the barrel itself. Under these conditions, and with individual jet tet ice

ports or openings in the outlet member directed outwardly at an angle of around 39 degrees from the common axis of the barrel and tube and with at least one jet directly axially downstream of the barrel, the liquefied gas and the liquid are thoroughly mixed to form the smothering and cooling mist or fog.

Desirably a single source of liquefied compressed gas is provided in accordance with the invention. It supplies gas under pressure to propel water or other liquid from the housing tank, and also the liquefied or partially liquefied gas to the interior of the gas supply tube to be mixed with the water and projected as a fog as above described. In the preferred form of the invention there is provided normally closed valve means controlling flow of water from the housing tank, and such valve means are openable by gas pressure from the source. Thus, interruption of fluid flow from the liquefied gas source causes, virtually simultaneously, cessation of jetting gas fiow from the jet ports of the outlet member, cessation of propelling gas pressure on the water in the tank, and closing of the valve in the water line.

It is also a feature of the invention to provide, in "a fire extinguisher of the character referred to, a pulsating valve for controlling the flow of liquefied nonfiammable gas. Such a valve may be adjusted to provide approximately one-half on time and one-half off time, in a cycle of from one or two seconds to about five seconds, depending upon the environment in which the fire has occurred. Such a pulsating or int rmittent flow is generally at least effective as a constant flow of a smothering and cooling fog, and an extinguisher of a given size can hence produce the fog over a substantially longer time, about double the time when a 50 percent cycle is used, than in the case of a continuous discharge of the fog.

Accordingly, it is a principal object of the present invention to disclose novel constructions of a fire extinguisher of the type producing a smothering and cooling fog of a liquefied nonflammable gas and a liquid such as water. Other objects and purposes of the invention are to provide, in such a fire extinguisher, an improved gun construction including a nozzle having an outlet member provided with a plurality of outwardly inclined jet ports and at least one axially directed jet port co'axially mounted in the water passageway in the gun; to provide in such a fire extinguisher a liquid mixture of water and a flammable material for increasing the efficacy of fog formation and vaporization of the water; to provide in such a construction means permitting intermittent flow of the fog and thereby lengthening the usable period of time of the extinguisher; to provide in the water supply line of a fire extinguisher of the above class a normally closed valve, openable by gas pressure, for opening and closing the Water supply line virtually simultaneously with supply and interruption of the liquefied compressed gas flow to the nozzle; to provide such a construction permitting reuse of the extinguisher several times for a single charging thereof; and for other and additional purposes as will be clear from a reading of the following description of preferred embodiments of the invention taken in connection with the accompanying drawing in which:

FIG. 1 shows a fire extinguisher construction, partially in section, in accordance with the present invention, the supply of liquefied compressed nonfiarnmable gas being shown in diagrammatic form, and portions of the con- 3 In FIG. 1, there is indicated generally at a source of pressurized. liquefied carbon dioxide including valve means for controlling the same, the liquefied carbon dioxide being supplied from source iii through flexible hose to a gun indicated generally at A housing tank for water is indicated generally at 60 and is connected to the gun through a flexible water supply hose 48. Coaxially mounted within hose 48 is a flexible tube 49, desirably made of copper or equivalent material, and adapted to lead pressurized liquefied carbon dioxide from the gun 30 to the water housing tank 6% in order to expel the water from the tank through hose 43 to the gun during operation.

The source 10 includes a container 11 for compressed liquefied carbon dioxide, a control valve 12. and a pulsating or intermittent valve 14. The control valve 12 is here shown as operated by a plunger 15, but it is to be understood that the precise means used for commencing fiow of liquefied pressurized carbon dioxide from the container 11 are not of themselves important in the present invention; a gravity-actuated piercing means such as that shown in my patents referred to previously may be used. The pulsating valve 14 provides intermittent flow of the liquefied pressurized gas as desired by the operator, or is adjustable to provide its continuous fiow. Agm'n, the details of the pulsating valve are well known in the valve art and form no part of the present invention.

The gun 30 includes a grip or handle portion indicated generally at 31 and a barrel or nozzle portion indicated generally at 32. Within the grip 31 there is provided a conduit 33 into which liquefied compressed gas from hose 20 is fed through conventional coupling means 34. The upper end of the conduit 33 is in communication with the rear end of a conduit 35 formed in a forwardly extending tube indicated generally at 3". The tube 36 is provided on its forward end with a coaxially-mounted tubular outlet member 37. The forward portion of outlet member 37 includes a plurality of jet ports for discharge of liquefied gas in accordance with the present invention.

As best seen in FIG. 2, the outlet member 37 includes a coaxially extending conduit 33 in communication with the conduit 35 of tube 36. The outlet conduit 38 is provided with a forwardly directed jet discharge port 3') and a plurality of jet discharge ports projecting angularly from the common axis of the outlet member 37 and barrel 32. Two of the angularly directed jet ports are indicated at and 41, and a total of four such ports desirably equally spaced circumferentially around the port 39 is a preferred number in accordance with the invention. Each of the angularly directed ports projects at an angle of approximately 30 degrees from the axis of the outlet member, so that the included angle between the axes of ports 40 and 41 as seen in the drawing is approximately 60 degrees.

The barrel 32 of the gun includes a tubular liner indicated generally at 4-2, terminating forwardly in an annular muzzle 43. The forward end of the outlet member 37 is recessed inwardly from the muzzle 43 by a distance approximately equal to the inside diameter of the cylindrical inner wall 44 of the liner. Thus, as seen in the drawing, the open space 45 between the forward end of the outlet member and the forward end of the liner is substantially a square and constitutes a fog mixing chamberor forming zone for the liquefied pressurized gas discharged through the jet ports including ports 39, 4t and 41 and the liquid such as water propelled outwardly through the barrel as will be later understood. In a typical embodiment of the invention, with a liner inside diameter of about 0.625 inch and an outlet member outside diameter of about 0.312 inch, the forwardly directed jet port 39 may have a diameter of about 0.110 inch, and the four angularly directed jet ports may have diameters of about 0.050 inch.

Referring further to the grip portion 31 of the gun, the water supply hose 4% communicates through conventional coupling means 4'7 with a conduit or water passageway 51 which extends in generally parallel relation with the liquefied compressed gas conduit 33 through the grip. The upper end of conduit 51 is in communication with a bore 52. formed in the rear portion of the barrel 32, the forward portion of the bore 51?. being in communication with the cylindrical conduit ormed in the liner 42.

in the lower portion of grip 31. there is formed a passageway 54 communicating with the liquefied compressed gas conduit 33. Passageway extends transversely of the grip, and tire upper end portion 55 of copper tubing 49 is in communication with the passageway 54, being held in position as shown by brazing or similar means 56. The grip may be provided with an access opening 57 closed by suitable plug means 58 in alignment with the passageway Thus, liquefied compressed gas existing in the passageway 5a is led through flexible tubing 49 to the water housing tank 60 previously referred to.

With detailed reference to the water housing tank 60, the tank body proper 62 may be generally of any suitable shape such as cylindrical, and the upper wall 64 is provided with an upwardly extending annular neck 65. The neck 65 is closed by a cover member indicated generally at 66, the latter being held in assembled relation as shown by an annular retaining ring indicated generally at 68 and threadedly connected at 70 to the upper outer portion of the neck 65. The cover 66 includes an upper enlarged boss portion indicated generally at 72, the boss being provided with a water passageway 74 communicating through conventional coupling means '75 with the hose 48. The cover 66 is axially bored to provide an upwardly extending passageway 76 communicating with the passageway '74, and at its lower end communicating through coupling means '78 with the upper end of a water pipe indicated generally at 80 and projecting downwardly within the housing tank 60.

The flexible copper tubing 49 coaxially carried within hose projects inwardly into the boss 72 and passes through an inclined bore 82, being hermetically retained in position by suitable brazing 83 and 84. The tubing then continues in a downwardly extending portion 86 into the water housing tank 60.

In accordance with the preferred form of the invention, there is provided within the water housing tank 60, gas-operated water flow control means. In FIG. 1 such means include a mounting bracket indicated generally at 90 carried on the lower end of the pipe 80, well above the bottom of the water tank 62. Bracket 90 includes a laterally projecting portion 92, and the hollow interior of the bracket is closed at its lower end by wall 93. The laterally extending portion 92 is connected to the interior of a valve body indicated generally at 94. To the upper end of valve body 94 is attached an actuating assembly indicated generally at 96 and extending upwardly from the valve. The actuator 96 is provided with a vertically extending cylindrical bore 98 closed at its upper end by closure means 100 having a central bore 162 in communication with the interior of downwardly extending tubing 86. Thus, compressed gas within tubing 86 is in communication with the upper portion of the interior of the actuator 96.

Slidably mounted within the cylindrical bore 98 of the actuator is a plunger piston indicated generally at 1 34 and provided with conventional sealing rings or the like and 106. The piston 104 is axially movable within the cylindrical. bore 98 between a lower position seen in the figure and an upper position thereabove. One or more gas escape orifices 108 are formed in the side wall of the actuator 96, thereby affording gas communication from the upper portion of the interior of the actuator to the interior of the water tank housing 60. When the piston 104 is in its upper position, the upper sealing means 105, at least, is above the level of the orifice or orifices 1%, thereby blocking the communication between the interior of the actuator and the interior of the tank.

Means are provided for resiliently biasing the piston 164 upwardly, and in the present illustration such means include a longitudinally extending helical spring indicated generally at 110 and surrounding a downwardly projecting piston rod 112. fixed at its upper end to the lower portion of the piston N24 and fixed at its lower end to a valve closure member 114. A conventional sealing gland member 116 may be provided in the lower portion of the actuator 95, through which the piston rod 112 may project.

The valve assembly or housing 94 includes an annular valve seat 121? which is directed downwardly. The valve closure member 114 mounted upon the lower end of the piston rod 112 is adapted, when the piston 1134 is in its uppermost position, to sealingly seat on the annular seat 129, and thereby block fluid communication past the valve. The closure member 114 is housed within a generally cylindrical member 122, to which the upper end of a downwardly extending pipe indicated generally at 124 is attached. Pipe 12 3 projects downwardly within the tank 6:), terminating at 126 fairly close to the bottom of the tank.

It will be seen that introduction of liquefied compressed gas such as carbon dioxide into the hose 26" from the source it) supplies such liquefied gas through the passageways 33 and 54 to the upper end 55 of the copper tubing 49 and thence to the upper portion of the valve actuator 96 within the tank 60. Pressure of such gas upon the upper face of piston 10-4 moves the piston downwardly into its position seen in FIG.1, thereby opening the valve closure member 114. Simultaneously, by exposing the orifice or orifices 1198, the pressurized gas is permitted to escape into the interior of the tank 6%), thereby exerting pressure upon the water therein and causing it to flow upwardly through pipe 124, past the open valve 114, and thence upwardly through pipe 80 and into the hose 58. The water then continues through the passageway 51 in the grip portion of the gun 39, through the passageway 52 of the gun and outwardly past the outlet member 37 previously described. The liquefied pressurized gas is also supplied, of course, to the interior of the tube 36 in the barrel portion of the gun, and thence outwardly in jet fashion through the jet ports such as 39, 4-4 and 41 to provide thorough mixing within the space 45 between the forward end of the outlet member 37 and the forward end of the liner 42. As a result, the gun emits a substantially homogeneous mist or fog, which is then readily vaporized by the heat of the fire in the fire zone.

In the form of the invention just described, it is desirable that the liquefied compressed gas supply valve 12 be closable by the operator. When so closed, the water control valve 94 within the tank 66 will be closed virtually simultaneously by reason of the restoring force of resilient means 11:) exerted upwardly against the piston 194. Thus the gun may be used to extinguish several fires over a period of time without the necessity of recharging the extinguisher after each individual fire. Moreover, the provision of the pulsating valve 14 in connection with the preferred form of the invention under discussion advantageously provides intermittent application of the fog to the fire. In many instances extinguishing of a fire can be accomplished just as quickly with such intermittent application as with continuous application of the fog, with an obvious advantage of econorny of use of the liquefied compresse gas and the water in the extinguisher.

An alternative form of the present invention is shown in FIG. 3. As there appears, the bracket 9%, the actuator 96 and the valve assembly 94 are eliminated, and the pipe 1% (corresponding generally to the pipe 8%) previously referred to) itself extends downwardly within the tank, its lower end 182 being close to the bottom of the tank. Moreover, the copper tubing 49 previously described extends coaxially within the pipe 180, as indicated at 184, the tubing continuing in a curved portion 186 and extending therefrom upwardly in portion 188 and terminating in a closed end 190. In the portion 188, and desirably generally in the upper portion of the tank 60, the tubing is provided with an orifice 192.

The remainder of the system with which the apparatus of FIG. 3 is used may be the same as that previously described in connection with FIG. 1. It will of course be understood that the bore 82 previously referred to in connection with FIG. 1 is omitted in the structure of FIG. 3. The pulsating valve 14 within the liquefied compressed gas supply means 10 finds its most valuable application in connection with the form of the invention first described and illustrated in FIG. 1.

It is also contemplated in the practice of the present invention to include in the water contained in the water housing tank 60 a quantity of flammable material to expedite the vaporization of the liquid portions of the fog during operation of the extinguisher. For example, the addition of from about 3% to about 10%, preferably about 5%, by weight of methyl alcohol is effective in this connection. Surprisingly, such addition of a flammable material to the Water in the tank 59 creates afog which is more effective than a fog of only water in smothering and cooling a fire and thereby extinguishing it. It is believed that the added material serves not only to somewhat reduce the boiling point of the water mixture, but also to more rapidly raise its temperature upon ignition of the flammable material, so that vaporization can more quickly occur and thus lower the temperature in the fire region by removing therefrom the heat of vaporization of the Water. An even greater proportion of flammable material may be added to the water with no important diminution of its fire extinguishing ability, up to around half of the total quantity of liquid in the tank 60, and this factor affords obvious and important advantages where the extinguisher must be stored and used in sub-freezing temperatures.

It is to be understood that the forms of the invention hereinabove described and illustrated are exemplary only, and that modifications and changes therefrom not departing from the spirit of the invention are intended to be embraced within the scope of the appended claims.

I claim:

1. In a fire extinguisher of the type adapted to project a cooling and smothering fog essentially comprising a liquid and a nonflammable gas, in combination:

a source of liquefied pressurized nonfla-mmable gas including means for controllably supplying liquefied gas therefrom;

a housing tank for liquid having an outlet opening and an internal pipe communicating the outlet opening with the lower portion of the tank;

a normally closed valve in said internal pipe and gas actuated means for simultaneously opening said valve and communicating compressed gas to the interior of the tank;

a gun for mixing liquid and gas to form a fog including a tubular barrel for directing the discharge of fog;

a flexible hose for communicating liquid from said outlet opening to said gun;

and flexible means communicating liquefied pressurized gas from said source to said gun and to said gas actuated means.

2. The invention as stated in claim 1 wherein said flexible means includes tubing extending generally coaxially within said hose.

3. The invention as stated in claim 1 wherein liquid in said tank comprises a mixture of water and a flammable material.

4. The invention as stated in claim 3 wherein said flammable material is methyl alcohol.

5. The invention as stated in claim 4 wherein the proportion of methyl alcohol to water is less than about ten percent by weight.

References Cited by the Examiner UNITED STATES PATENTS Echola 239429 Dunn 239-373 X Goddard 239-429 X Richards 239-432 X Griggs 16931 Jacobs 1699 Jacobs 16931 Holzinger 252-73 Brazier 16915 X Condo 252-73 X Carleton 222-400.7

EVERETT W. KIRBY, Primary Examiner.

EUGENE F. BLANCHARD, LOUIS I. DEMBO,

Examiners. 

1. IN A FIRE EXTINGUISHER OF THE TYPE ADAPTED TO PROJECT A COOLING AND SMOOTHERING FOG ESSENTIALLY COMPRISING A LIQUID AND A NONFLAMMABLE GAS, IN COMBINATION: A SOURCE OF LIQUEFIED PRESSURIZED NONFLAMMABLE GAS INCLUDING MEANS FOR CONTROLLABLY SUPPLYING LIQUEFIED GAS THEREFROM; A HOUSING TANK FOR LIQUID HAVING AN OUTLET OPENING AND AN INTERNAL PIPE COMMUNICATING THE OUTLET OPENING WITH THE LOWER PORTION OF THE TANK; A NORMALLY CLOSED VALVE IN SAID INTERNAL PIPE AND GAS ACTUATED MEANS FOR SIMULTANEOUSLY OPENING SAID VALVE AND COMMUNICATING COMPRESSED GAS TO THE INTERIOR OF THE TANK; A GUM FOR MIXING LIQUID AND GAS TO FORM A FOG INCLUDING A TUBULAR BARREL FOR DIRECTING THE DISCHARGE OF FOG; A FLEXIBLE HOSE FOR COMMUNICATING LIQUID FROM SAID OUTLET OPENING TO SAID GUN; AND FLEXIBLE MEANS COMMUNICATING LIQUEFIED PRESSURIZED GAS FROM SAID SOURCE TO SAID GUN AND TO SAID GAS ACTUATED MEANS. 